Preparing arsenobenzene derivatives which are stable in solution



Patented Aw; 26, 1924.

UNITEDv STATES PATENT OFFICE.

KARL STREITWOLF, OF FRANKFURT ON THE MAIN, GERMANY, ASSIGNOR TO FARE- WERKE VORM. MEISTER LUCIUS do BR'U'NIN'G, OF HOCHST ON THE MAIN, GER- MANY, A CORPORATION OF GERMANY.

PREPARING ARSENOBENZENE DERIVATIVES WHICH ARE STABLE IN SOLUTION.

No Drawing.

To all whom it may concern:

Be it known that I, KARL Srnnrrwonr, Ph. D. apothecary, a citizen ofGermany, residing at Frankfort on the Main, Gunters- I burg Allee 50, Germany, have invented certain new and useful Improvements in Preparing Arsenobenzene Derivatives which are Stable in Solution, of which the following is a specification.

In United States Patent No. 1,431,671 of 1922 and German Patent No. $75,718 is described a process according to which preparations of an excellent stability are obtained by combining sulfoxylate compounds of any arsenobenzenes with any arsenobenzenes.

Now we have found that by the combination of formalydehydebisulphite compounds of arsenobenzenes with any arsenobenzenes there are also obtained products of excellent stability and of eminent "therapeutic efi cacy. The combination may be efiected either in a dry state or in solution or suspension.

Examples.

(1.) 3.0 of the monoformaldehydebisulphite compound of dioxydiaminoarsenobenzeneare dissolved in 10 com. of H,@ and there are further dissolved 3 of the silver compound of the sodium sa t of ,dioxydiaminoarsenobenzene also in 10 com. of H 0. Both solutions are then combined and allowed to stand for one hour in an atmosphere of nitrogen, if required, while heating. The solution is then introduced in about 11} litres of alcohol and the precipitate is separated. The compound thus obtained is a brown to brownish-black powder, which is soluble in water with alkaline reaction and insoluble in alcoholic ether. Carbon dioxide does not.cause any precipitate from the aqueous solution.

Instead of the monoformaldehyde comv Application filed September 17, 1923. Serial No. 663,292.

Water 5 g. of the silver-sodium compound of dioxydiaminoarsenobenzene. Both solutions are combined and allowed to stand for one hour under nitrogen, if required, while heating. The solution is then introduced into 12; litres of alcohol and the precipitate is filtered ofi'. The compound thus obtained is a brown to brownish-black powder, clearly soluble in water. The solution remains clear while introducing carbonic acid.

(3.) 5 g. of monoformaldehydebisulphite of the p-arsenodi-(l-phenyl-QB-dimethyl-tamino-fa-pyrazolone) are dissolved in 15 com. of water and this solution is combined with the solution of 5 g. of the silver-sodium compound of dioxydiaminoarsenobenzenk also in 15 com. of water. The solution is allowed to stand for one hour under nitrogen, if required, while heating and then precipitated with 19 litres of alcohol. The substance obtained is a brown powder, clearly soluble in water. The solution remains clear when introducing carbonic acid.

(4.) 4,5 g. formaldehydebisulphite of the 4 .4 bismethyl -amino-3 43 5 .5-tetraaminoarsenobenzcne, having the structural formula:

nmANmcmsoma Hm are dissolved in 25 ccm. of water and to this solution there are added 4,5 g. of the silversodium compound of the dioxydiaminoarsenobenzene dissolved in 25 com. of water. The solution is allowed to stand for one hour under nitrogen, if required, while heating. The substance is recipitated with 1% litres of alcohol and t e precipitate is filtered ofi. The compound thus obtained ,is a brown powder, clearly soluble in water. The 20 solution remains clear when introducing carbonic acid.

Having now described my invention .what I claim is: y

The process of makin arsenical pre :1.- 26 rations which are stable in solution, wh1ch comprises combining the silver-sodium salt of 4,4-dioxy-3,3'-diamino-arsenobenzene with a. formaldehyde-bisulphite compound of. anarsenobenzene.

In testimony whereof, I afiix m-y signature- KARL STREITWOLF. [1 s.] Witnesses:

C. G. L. B. Wms, PAUL A. WILLIAMS. 

